Voyager 2 became the longest-operating spacecraft on August 13, 2012, surpassing Pioneer 6, which launched December 6, 1965 and sent its last signal back in 2000 after 12,758 days of operation.

The Voyager spacecraft are on the verge of entering interstellar space after reporting back from NASA about the prevalence of high-energy particles seeping through to the Solar System. This change indicates an increasing pace in Voyager 1's environment.

The Voyager NASA scientists are analyzing data on the direction of the magnetic field, which they believe will change upon entry into interstellar space.

Although an intriguing feat lies before it, Voyager 2 has had many notable discoveries during its venture to the abyss.

"Voyager results turned Jupiter and Saturn into full, tumultuous worlds, their moons from faint dots into distinctive places, and gave us our first glimpses of Uranus and Neptune up-close," Stone said in the release. "We can't wait for Voyager to turn our models of the space beyond our sun into the first observations from interstellar space."

Voyager 2 is about 9 billion miles away from the sun, heading in a southerly direction, while Voyager 1 is about 11 billion miles away from the sun, heading in a northerly direction.

For the past five years, the spacecraft have been exploring the outer layer of the heliosphere, which is the giant bubble of charged particles the sun blows around itself.

"We continue to listen to Voyager 1 and 2 nearly every day," Suzanne Dodd, Voyager project manager at NASA's Jet Propulsion Laboratory, Pasadena, California, said in a press release. "The two spacecraft are in great shape for having flown through Jupiter's dangerous radiation environment and having to endure the chill of being so far away from our sun."

The scientists at NASA have been managing the use of power from the continually diminishing energy sources on the two spacecraft. They believe the Voyager twins will have enough electrical power to continue collecting data and communicating it back to Earth through 2020, which kind of makes the Energizer bunny look a little foolish.